Undetectable Guns May Soon Be Legal — but Caveats Apply

Unless Congress takes action, in less than a month it will be legal under federal law to own a plastic gun made with a 3D printer — a gun that could be untraceable by metal detectors, could kill a person, and could blow your hand apart.

Unless Congress takes action, in less than a month it will be legal under federal law to own a plastic gun made with a 3D printer — a gun that could be untraceable by metal detectors, could kill a person, and could blow your hand apart.

When the Undetectable Firearms Act was passed in 1988, it was in response to the creation of the Glock 17, a weapon made with plastic composite components, as CNet explains. The idea that a weapon could be constructed entirely of plastic — thereby evading metal detectors — meant a requirement that every weapon contain at least enough metal to show up in detection devices. When the libertarian tech group Defense Distributed unveiled plans for a 3D-printable gun earlier this year, its instructions mandated that the device contain a hunk of metal to meet that requirement. If the Undetectable Firearms Act isn't renewed, a weapon without that hunk of metal would no longer be illegal.

The advent of 3D printing — and the work of Defense Distributed in particular — has given the issue new urgency in the government. As New York Rep. Steve Israel argued earlier this month, "in 1988, the notion of a 3-D plastic gun was science fiction. Now, a month away [from the law's expiration], it is reality."

Israel sponsored legislation in the House to continue the ban. In an unsubtle effort to bolster legislative efforts, the ATF on Wednesday announced the results of its tests with 3D-printing, as reported by the Huffington Post. The test results can be summarized with the silent video below.

That's the Defense Distributed "Liberator," built on a 3D-printer using a plastic produced by a company called Visijet. Had you been holding that in your hand and pulled the trigger, there would possibly be fingers flying away in slow motion as well. Using more robust plastics, the ATF's firing tests saw more success. The results, according to the Huffington Post: "the weapon, while not quite as powerful as most guns, could penetrate several inches of soft flesh as well as a human skull." It also created 3D-printed designs for a weapon that could fire shotgun shells, and predicted that a system for an automatic weapon could be forthcoming.

The ATF's argument that a gun could be printed and carried into secure areas is not without merit. A plastic gun was snuck onto the floor of the Israeli Knesset in July — twice. The Daily Mail brought one onto a train in Britain. Sneak in a plastic gun made of robust enough plastic, and you could do some serious damage — perhaps even legally. (The UFA expiration mostly affects the legality of possessing a weapon. Whether or not printing a plastic gun would be legal is another question.)

But there remain a number of serious caveats, at least for the time being. As we have noted, printing such a weapon is still very difficult for all but the most serious hobbyists. Nor is the idea of mandating metal parts likely to be much deterrent to a criminal that wanted to build a weapon for the purposes of, say, assassinating a political target. The Department of Homeland Security issued a similar warning to the ATF's earlier this year, noting that "limiting access" to printed weapons "may be impossible."

The good news? These weapons are almost certainly of poor quality. The construction allows a lot of the force of the explosion that propels the bullet to escape from the barrel, meaning the bullet fires more slowly than form a traditional gun. Reloading the weapon is slow and cumbersome, even if the gun isn't damaged in the initial firing. (One experimental firing got off nine rounds — in about three hours.) And its accuracy is highly questionable. In other words, getting a gun into a secure area is one thing. Doing any real damage with it is another.

At least for now. The challenge that Israel and the ATF note is that 3D printers, 3D printing, and 3D-printing materials are all fairly young technologies. They will evolve. What the government and Congress hope to do is craft a law that will last as long as the one passed in 1988, covering eventual technological developments. That's a tall order.

This article is from the archive of our partner The Wire.

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